St.amand, J.

Space shuttle GN and C equation document no. 20: Fine alignment gyro torquing angles

The procedure for aligning the inertial reference unit of the space shuttle by celestial references is discussed. The gyro torquing angles required to go from the present stable member to the desired stable member are determined. The inputs are the transformation matrix from the reference to the desired stable member coordinates and the unit vectors to the two target stars in both the reference and present stable member coordinates. The equations involved in establishing the reference are developed.